body,
html {
	width: 1350px;
	background-color: #fff;
}

ul,
li {
	list-style: none;
}

h1,
h2 {
	font-weight: 400;
	font-family: "Microsoft YaHei";
}

.header_status {
	height: 40px;
}

.header_status .nav_item {
	height: 40px;
	line-height: 40px;
	color: rgba(255, 255, 255, .6)
}

.header_status .nav_item:hover {
	color: white;
	background: #666666;
}


.head-01 {
	position: relative;

}

.title-box {
	position: absolute;
	display: block;
	text-align: center;
	right: 380px;
	top: 60px;
}

.title-box h1 {
	font-size: 40px;
	color: #fff;
	text-shadow: 0 2px 4px rgba(28, 31, 33, .6);
}

.title-box h2 {
	font-size: 16px;
	color: #fff;
	text-shadow: 0 2px 4px rgba(28, 31, 33, .6);
	margin-top: 8px;
}

.head-01 .play-box {
	position: absolute;
	top: 200px;
	left: 100px;
	width: 1152px;
	height: 120px;
	background-color: rgba(255, 255, 255, .86);
	box-shadow: 0 8px 16px 0 rgba(28, 31, 33, .1);
	border-radius: 20px;
}

.head-01 .play-box span {
	margin: 50px 25px;
	display: inline-block;
	font-size: 15px;
}

.head-01 .study-btn {
	position: absolute;
	top: 238px;
	right: 190px;
	background: #f01414;
	border-radius: 24px;
	padding: 12px 48px;
}

.head-01 .aa {
	font-size: 16px;
	color: #fff;
	line-height: 24px;
	font-weight: 700;
}

.head-01 .aa:hover {
	background: rgba(240, 20, 20, .8);
}

.course-section .course-ul {
	margin-left: 280px;
}

.course-section .course-ul .course-item {
	display: inline-block;
	margin-top: 80px;
	margin-left: 20px;
	width: 144px;
	height: 68px;
}

.course-section .course-ul .course-item {
	font-size: 18px;
	font-family: "微软雅黑";
}

.course-section .course-ul .active a {
	color: #f20d0d;
}

.course-info {
	/* background-color: grey; */
	margin: 0 100px;
}

.course-info .course-list .list-item {
	position: relative;
	overflow: hidden;
	padding: 32px 0 20px 0;
	z-index: 2;
	vertical-align: middle;
	border-bottom: 1px solid rgba(28, 31, 33, .1);
}

.course-info .course-list .list-item img {
	position: absolute;
	display: block;
	top: 16px;
	left: 12px;
}

.course-info .course-list .list-item .name {
	font-weight: 700;
	font-size: 16px;
	color: #07111b;
	margin-left: 70px;
	margin-bottom: 8px;
}

.course-info .course-list .list-item .course-desc {
	margin-left: 70px;
	margin-bottom: 16px;
	line-height: 24px;
	font-size: 14px;
	color: #07111b;
}

.course-info .course-list .list-item .list-item-content ul {
	padding: 0;
	margin-left: 70px;
	border-top: 1px solid rgba(28, 31, 33, .1);
	line-height: 24px;
}

.course-info .course-list .list-item .list-item-content ul li {
	padding: 12px 0;
	border-top: 1px solid rgba(28, 31, 33, .1);
	line-height: 24px;
}

.course-info .course-list .list-item .list-item-content .play-btn {
	float: right;
	margin-right: 80px;
	padding: 0 16px;
	font-size: 12px;
	background: rgba(242, 13, 13, .1);
	border-radius: 12px;
	color: #f20d0d;
	font-weight: 700;
}

.course-info .course-list .list-item .list-item-content .play-btn:hover {
	color: #fff;
	background: #f20d0d;
	cursor: pointer;/* 光标呈现为一只手 */
}

.course-info .course-list .list-item .list-item-content .title_info {
	display: inline-block;
	max-width: 600px;
	overflow: hidden;
	text-overflow: ellipsis;
	white-space: nowrap;
	vertical-align: middle;
}
.arrow-up{
	position: fixed;
    bottom: 10%;
    right: 0;
    z-index: 9;
    background-color: #fff;
    box-shadow: -2px 2px 5px 3px rgba(7,17,27,.1);
}